Chesapeake Energy (CHK-6.5%) is sliding on heavy volume. Reuters reports the SEC's Texas office has been demanding documents from Chesapeake as part of the agency's probe into the company's deals with CEO Aubrey McClendon. Meanwhile, Baker Hughes (BHI+9.4% - previous) reports the rig count for U.S. natural gas wells has fallen to 518 thanks to weak prices. That figure is down 45% from October's high, and represents a 13-year low.